1. Field of the Invention
This invention relates to organic semiconductor devices and to methods for making such devices.
2. Description of the Related Art
Many electronic applications require complex circuits with many active semiconductor devices. Advances in the fabrication of complex integrated circuits (ICs) have become possible through the development of technologies for making and using complex masks to etch thin films. In inorganic technologies, mask-controlled etching enables the fabrication of a complex pattern of physically disjoint inorganic semiconductor regions from an initially continuous thin film of the semiconductor. From the disjoint semiconductor regions, separate active semiconductor devices are constructed.
In organic technologies, masks and etching have not been as successful in advancing the fabrication of complex ICs. In particular, mask-controlled etches have not produced fine patterns of some desirable organic semiconductors from thin films. For example, pentacene has desirable electrical properties, because pentacene-based. FETs typically have high ON/OFF current ratios and active channels with high mobilities. Nevertheless, mask-controlled etching techniques have not been very successful in dividing thin pentacene films into fine patterns of disjoint regions. Such processes either have degraded the pentacene films or have not been cost effective. For that reason, pentacene has limited usefulness in organic ICs, i.e., thin film ICs. It would be desirable to incorporate such desirable organic semiconductors into thin film ICs.